The game's official title logo reads like "Honkai 3rd Impact" when read directly from left-to-right ("Honkai 3rd") then-down ("Impact"). Sounds odd at first, but then you realize it would mention "Third Impact" and be reminded of Neon Genesis Evangelion if you're even a bit familiar with that series. note In Eva, the "Third Impact" is the feared scenario where an Angel makes contact with Adam and annihilates all life on the planet, and which eventually does happen in The End of Evangelion but under different circumstances Going further, this game has a lot of intentional Evangelionreferences, as mentioned in the Shout-Out page. Everything came in full circle when the Version 4.5 update of Honkai Impact 3rd officially featured a crossover collaboration event with Evangelion, complete with a playable Asuka, and some Eva-themed event story, Stigmata, Weapon, and alternate outfits.
The gene construct used to create Super Soldiers in the "M.A.N.T.I.S." Project is called "Intra-Chromosomal Honkai Repeats" and has the acronym of ICHOR. Siegfried is also noted to have ICHOR infection because of his dormant Kaslana genes. This alludes to Greek Mythology, wherein Ichor is the golden fluid that flows as the blood of the gods, but is toxic to mortals.
The game uses the German word "Herrscher" to refer to the "Rulers", i.e. the human harbingers of Honkai. It starts making sense considering 1) it's most likely the European organization Schicksal who first named the term, and 2) the very first Herrscher (at least in the current era) appeared in Berlin.
The name of the World Serpent organization makes sense as the one who founded it was Gray Serpent, Mobius' creation, and Mobius was a Flame Chaser from the Previous Era who had a heavy snake theme that she presumably passed down or also gave to her creation.
Chapter 28's revelation of Bianka Ataegina (a.k.a. "Durandal") being the original Kiana Kaslana retroactively creates two sets of parallelisms. One between her and Cecilia Schariac (her mother), while the other is between Siegfried Kaslana (her father), and K423 (her clone sister, a.k.a. The Protagonist "Kiana Kaslana"):
Durandal is the current wielder of the Abyss Flower Divine Key just as how her mother, Cecilia Schariac, was a previous wielder of the Abyss Flower. It makes the Abyss Flower an Ancestral Weapon and highlights a mother and her daughter being lance-wielders.
Siegfried once used the Judgement of Shamash, a Divine Key that can transform between two handguns and a flaming greatsword; Kiana primary fights using dual handguns, but as the Herrscher of Flamescion, she fights using a flaming greatsword.
The song "Moon Halo" is one of the most hopeful insert songs in the game, since it references every Valkyrie theme before it and contrasts their tone with a far more optimistic outlook. However, there is one peculiar line that really rings a bell: "Turned into a moon that always tells the warmth and brightness of the sun". While the line itself is optimistic like the rest of the song, for those who played A Post-Honkai Odyssey, the line also contains an ominous yet bittersweet feeling, possibly foreshadowing Kiana's ultimate fate referenced in the game mode's backstory where she has to relocate 99% of Honkai to the moon, but she will never see her friends and loved ones again.
